Hi All,

I just turned 90K on my 2003 Cooper S. From the sound and visual check at the muffler shop, it appears that the cat has sprung a leak. But I'm not sure as I haven't been able to remove for a closer inspection. Anyway, I need get the problem sorted out as my Mini sounds really bad.

A couple questions. First, has anyone ever tried to repair by cutting out and replacing the cat? I know it sounds far fetched, but I've seen some amazing things done at a good muffler shop.

OR is there anyone out there that has replaced their stock header & cat with an aftermarket replacement that would be interested in parting with it?

Lastly, if anyone has any other ideas on how to correct the problem (besides the obvious) I'd appreciate hearing from you.

Cheers,

Mike @ Moss

 

Not sure how an aftermarket cat would hold up with these cars. Maybe you can find one with a want ad in the marketplace once you figure out if that's that cause or not.

Some guys rip them out for race cats ect.

 

I too just discovered the same problem on my 02 MCS. My crack is in the weld just under the heat shield at the pre-cat. It's about 75% around and going fast. My question is, I'm more apt to modding the car, so would an aftermarket header be a good choice or would that put to much pressure on the stock mufflers? I can't afford to get a whole system right now as I have other stock problems higher on the list. Sorry OP, if I hijacked your thread

 

haha yeah i had this happen to me last week... right after the pre-cat the pipe just disconnected. fell off. yep.
took it to a muffler shop and they just welded it back on in as many spots around it as he could and then i got some of this glue from auto-zone (in the exhaust repair section) and filled in the holes.

worked like a charm.. although it isnt the greatest solution.
the check engine light was on and as soon as i got that goo stuff on there and let it dry, the light went off. and i had the state inspection done a couple days afterwards and it still passed. i spent a total of 45 dollars to fix this.. wasnt too bad.

if i had the money though i would definitely replace the headers all the way back...

 

That's American enginuity right there!

I'm betting there's going to be more threads like this soon. Could it be the 100,000 mark taking its toll? I'm wondering if an engine dampener will help prevent this.

I decided to save some bucks for the impending clutch job and found a specialty muffler shop nearby. It's a one man operation but the guy has been welding for years and really knows his stuff. He does a lot of marine systems as well as cars. He was cool enough to fix it on a Saturday which are not his posted hours and even let me shoulder surf while he worked (I did my best to keep quiet and not pester him). He wanted to take off the manifold because of the lack of room and he wanted to be sure he was hitting the crack well. He even let me do some of the prep work since he was finishing up a previous job when I got there.

The manifold bolts came out nicely after a good hour or two soak with a lube I think was called Moose Milk. The mech's main concern was that some catalyics have ceramic internals which can take a lot of heat but some are other materials. He seemed convinced the catalytic had non-ceramic material upon visual inspection. Since he wasn't sure what the pre-cat held he decided to weld it at low heat to be cautious. He welded a little at time, allowing it to cool between welds. He was able to get a bead on it. Not pretty but sealed it up good. We slapped it back on and now she's purring like a kitten. No dash lights or codes before or after. Woohoo! I'm back baby!